Overweight women are at greatest risk of retaining weight gained during pregnancy. Postpartum weight retention further exacerbates these women's lifetime risk of obesity and related morbidities. The postpartum period may be a special "teachable moment" for promoting weight loss. Postpartum changes in weight-related affect, risk perceptions, and self esteem may increase women's receptivity to and success with weight loss. However, in the absence of formalized interventions, postpartum changes in these factors could also undermine weight loss (e.g., added demands of child care may hinder physical activity and proper meal planning). Thus interventions are needed that leverage naturally occurring postpartum weight changes to encourage increased physical activity and adoption of a healthy diet, to accelerate and/or increase postpartum weight loss among women at-risk for lifetime obesity. Moreover, the extent to which postpartum is a teachable moment that may modify the efficacy of formal intervention should be investigated empirically. To this end, proposed is a two-arm, five-year randomized intervention trial. Primiparous women, overweight or obese prior to pregnancy, who delivered healthy infants at a Duke clinic, are the target population. 400 women will be recruited, stratified by racial group (white/other and African American), and randomized to: MINIMAL CARE: a 12-month subscription to a new mothers health magazine, or the ACTIVE MOTHERS POSTPARTUM (AMP) INTERVENTION: the magazine subscription, 10 ACTIVMOMS physical activity sessions, 8 Mom's Time Out nutritional sessions, a sport stroller, and 6 telephone counseling calls. Primary aims are to evaluate whether AMP can: 1: promote greater weight loss 12-months post-intervention (p.i.). 2: increase physical activity at 1 month p.i. 3: lower calorie intake overall, and from fat, at 1-month p.i. The secondary aim is to assess whether participation in the intervention and weight loss is greatest among women for whom the transition to postpartum is a "teachable moment." Women will be identified and screened for eligibility by chart review and telephone at 32-36 weeks of pregnancy. Participants will be surveyed at 8 weeks postpartum (pre-intervention baseline) and at 1, 6 and 12 months p.i., If effective, the AMP intervention can be disseminated in health and community centers common in both rural and urban communities. In addition, extended follow-up will enable evaluation of long-term benefits of the intervention for weight loss and maintenance.